Process of removing suspended matter from gaseous fluids.



H. L. DOHERTY. PROCESS OF REMOVING SUSPENDED. MATTER FROM GASEOUS FLUIDS.

APPLICATION FILED APR.13, 1911.

1,071,893, Patented Sept. 2, 1913.

F i 101140 an ID witueoowwm Henry L. Dnhertx, Svvuewtm 3513 his 613011421 HENRY Ia. DOHEBTY,

OF NEW YORK, N. Y.

PROCESS OF REMOVING SUSIPENDED MATTER FROM GASEOUS FLUIDS.

Specification of Letters latent.

Application filed April 13,

V Patented Sept. 2, 1913. 1911. Serial No. 620,861.

Processes of Removing Suspended Matterfrom Gaseous Fluids, of which the follow ingis a specification.

This invention relates to a process of removing suspended matter from gaseous fluids, and, in particular, to a type of such process in which the gaseous currentis caused to follow a spiral path.

The object of my invention is to provide an improved process for separating from a gaseous current substantially all of the suspended liquid and solid particles which it contains, with special reference to the removal of tar and dust particles from illuminating gas.

In my invention which is the subject of Letters Patent No. 798,667, dated Sept. 5th, 1905, I have revealed an apparatus for accomplishing the above object by passing the gaseous current through a helical passage at a rapid rate, whereby a rapid rotary motion is given to the current and the suspended liquid and solid particles are thrown off by the centrifugal force thus developed. In my co-pending applications Ser; Nos. 535,842 and 535,843, filed Dec. 31st, 1909, 1 have shown improvements on the invention referred to above by virtue of which I am enabled to communicate a whirling mot-ion to the gas by causing it to traversea spiral passage. This present invention relates to a modification of the latter invention by virtue of which I am enabled to communicate a whirling motion to the gas first in one direction and then in the other by causing it to traverse a double spiral passage-the gas passing through one passage from the peripheral extremity to the inner of the one passage and thence back to the peripheral extremity of the other assage, or vice versa.

In the accompanying drawings I have shown a. form of apparatus forapplying the process of my invention. which apparatus I have claimed in application Ser. No. 688538. filed Apr. 1th. 1912. the present application being limited to the process.

Figure 1 is a vertical cross-section of the apparatus on the line A-B of Fig. 2. Fig.

2 is a horizontal cross-section on the. line C-D of Fig. 1. Fig. 1s a part vertica proper.

diametral cross-section on an enlarged scale ing the device for providing a film of liquid on the spiral surface when the gas treated does not contain liquid in suspension, or when it is desired to treat the gas with an absorbentliquid of special character.

l1 designates the separating chamber Attached to 1 is a sheet, 2, having aipartition. 5, which forms the gas inlet and outlet chambers, numbered 3 and 4 respectively. A vertical slot is cut in the wall of chamber 1 which extends the full height of chambers 3 and 4: and forms the gas inlet and outlet ports, numbered 6 and 7 respectively. Attached to partition 5-is the peripheral termination of a s iral wall, 8. Another spiral wall, 9, para] el to 8, is at.- tached to the wall of 1 at the side of port 7. There are thus formed two spiral I assages, 10 and 11, which serve as inflow and outflow passages for the gas. As shown, these passages are in communication at the axial part of 1 and may be usedinterchangeably. Passage 10 communicates with chamber 3 and passage 11 with chamber 4. With the arrangement of the apparatus shown, 12 is the gas inlet pipe, 13 the gas outlet pipe.

14 and 15 are pressure gages in communication, respectively, with chambers 3 and 4.

16 is a gage indicating the level ofthe liquid in tank 1.

.17 is the pipe through which liquid is supplied to the tank 1. and 18 is the pipe through which liquid is withdrawn from tank 1.

19 is a cock on 18 which is arranged to be actuated through the rocking arm 20 by the relative movement of the lifts of the two small gas holders in communication with the inlet passage 12 and outlet passage 13. respectively. The stem, 20, of cook 19 bears the rocking arm 21. The ends of 21 are con: nected respectively with lifts of the small gas holders. of which one, numbered 23, is shown in art.

24 is a tar separating chamber which separates the heavy tarry matter from the liquor drawn off from the separator. A battleplate, 24'. in 2% prevents the direct flow of liquor from the inlet pipe 18 to the outlet 25. 24 is another baille reaching nearly tothe bottom of 24 but leaving a passage. 2}."through which the tar chamber 26 and the li qqor chamber 26 communicate.

.j-tartoiects in the bottom of 26 :ield passes of 'thc upper ortion of the apparatus show--- The thence into 26 through 27 as tar is withdrawn through 27. The tar-tree liquor is drawn off from 24 through the pipe 25 and raised by the circulating pump 28 to the reservoir 31 through the pipe 29. Any surplus liquor which entt rs the system by condensation from the gas, or otherwise, is withdrawn through the overflow 31". The circulating pump 28 is thus always discharging against the head of liquid in reservoir 31. The reservoir 31 should have a'capacity such that the level of the liquid will not be materially affected by fluctuations in the circulation of the liquid, in order that a fairly constant head may be maintained on the valve 30'. When the liquid passing through the pump is below the normal quantity the deficiency is supplied by the liquid in 31. When the liquid passing through-the pump is greater than the normal quantity the excess enters the reservoir 31, again filling the latter.

10 and 11' are two pipes placed respectively ,in the spiral passages 10 and 11 through which Water or any other liquid may be 811 plied to establish a film of liquid on the spiral .walls of the separator when the gas itself does not contain liquid in suspension. In such case, liquid is supplied to the separator through the pi es 33 and Deflcting sheets, 10 and 11 respectively, cause the liquid discharged from 10 and 11' to follow the respective spiral walls.

In the operation of the apparatus to carr .out my process, the gas is conducted to e separator through the pipe 12, flows through the chamber 3 and the spiral passage 10 to the central ortion of the chamher 1, back through tie spiral passage 11 to the gas outlet chamber 7 and thence discharges through the pipe 13. The movement of the gas may be efi'ected either by induced or forced draft, the requirement being sim 1y that there should exist a suiticient di erence in pressure between 12 and 13 to impart the required velocity to the gas. In this embodiment of my invention the method of operation is as follows: \Vater is sup lied to 1 from 31 through the pipes 30 and 17 until the gage 16 shows that the proper normal level of the liquid has been attained. The ump 28 is now started and cook 19 a djusted to its normal position. Additional water, if necessary, is run into tank 31. Valve 30' is adjusted s that the liquid just fails to flow through pipe ,1". The gas is turned on through the pipe 12. under the necessary pressure and enters the outer convolution of passage 10, passes to the center of the tank 1, as already rleserilitwt T and thence back through the pas-age ll to the outlet chamber 4, from which it discharges through the passage 1 .-\s the gas passes toward the. center of the separzo tor 1 it takes on a higher and higher angular velocity. Returning to the periphery through the passage 11 the a ngular velocitv of the gas diminishes with the increase ill the radiusof the circular path which it is traversing. From 4, the gas passes In any i other condensing and purifying apparatus which may be used. During lJilirlllLjC through the separator, the angular velocity communicated to the gas generates suliicient centrifugal force to throw :he suspendcd liquid or solid p2\l'il\"l( t the peri -iu-rv ol the gas stream and ltl -ltfUlC int wa t with the outer wall of the spiral. ihis soon becomes coated with a film of tar. which in turn assist); in the removal of other tar globules from a fresh portion of the gas. The simple projecti n of dust particles against a vertical wall would not effect entirely their withdrawal from the gas stream as the buoyant effect of the current of gas moving at a high velocity and the contact friction between the gas and dust would sweep the parti les along even while in contact with the wall of the passage. The tarry liquid, ln'nvever, possesses a considerable surface ten ion. and adheres to the wall with considerable tenacit;\'- sutlicient, in fact, to resist the tendency that the friction of the gas current has to sweep the deposited particles back into the current. This tarry film seizes the liquid globules and dust particles as they come in contact with the wall and withdraws them from the influence of the current of gas sweeping through the passage 7. As the deposit on the wall accumulates, the outer layer forms innumerable rivulets, or a continuous film, which run off into the liquid seal in the bottom of l. The

force of adhesion betweer the tar .and wall,

however, suffices to keep the latter coated with a comparatively thick continuous film.

Having described my invention, what I claim is 1. The process of separating from a body of gaseous fluid particles suspended therein, which consists in imparting a spiral motion to the said gaseous fluid first in one direction of rotation and then in the. opposite direction.

2. The process of separating from a body of gaseous fluid particles suspended therein, which consists in causing the said gaseous fluid to traverse a spiral path from the peripheral extremity toward the point of origin of the said spiral. and thence trav ersc a second spiral path from the inner to the peripheral extremity of the same.

3. The process of separating from a body of gaseous fluid particles suspended therein. which consists in imparting to the said gaseous fluid, first. a gradually accelerating L angular motion and then subjecting the said gaseous fluid to a gradually decelerating angu ar motion.

1. The process of separating from a body ziJ which consists in imparting an angularmotion to the said gaseous fluid, gradually accelerating the said angular motion to a.

maximum, and then gradually decelerating the said angular motion to a minimum.

5. The process of se arating from a body of gaseous fluid partices suspended therein, which (:onsists in imparting akspiml motion to the saidlgaseous' fluid first in one direction df rotation and then inthe ofiposite direction, rind at the'same time contacting the said gaseous fluidwitha film of liquid.

6. The process ofsepa'zwtin from a ,body of gaseous fiuidparticles suspended therein, which consists in causing the said gaseous fluid-t0 traverse a spiral path from the pe- .ripheral extremity to the point of origin of said? spiral and thence traverse a second spiral pathv'fronithe inner to the peripheral extreinity of the samei and duringfthe said travel ofthe gaseous fluid contacting the same with a film-0f liquid.

7 The process of separating from a body of gaseousfiuid particles suspended therein, 7

which conslsts in imparting to the said gaseous fluid a gradually accelerating angular motion and then subjecting the said gaseous fluid to a gradually decelerating angular motion, While at the sameftime contacting the'said gaseous fluid with a film of liquid.

8. The process of separating from a body oi gaseous fluid particles suspended therein, which consists in imparting an angu'larmot-ion to the said gaseous fluid, *graauallyaccelerating the said angular motion to a maximum, then gradually-decelerating the saidjangular motion to a minimum, the said gaseous fluid'being contacted with a film of liquid While iindergoing'said angular motion;

Signed at New York city in the county of New York and State of NewYorh this 12th day of April A. D. 1911.

J. M. MGMILLIN, F. L. BLACKBURN. 

